Georg Dubacher and Roland Regli show a piece of a geothermal probe, almost 200 of which are bored 320 meters deep into the ground.
New standards for carbon-neutral solutions
The Papieri site has an energy system that is one of a kind within Switzerland: all of the energy required for heating and cooling and almost half that required to cover the development’s electricity is generated on site. Pulling off this gargantuan feat takes people with real creativity and vision. We have profiled two of them for you here: the energy consultant and the mastermind behind the Papieri energy system, Georg Dubacher, and Head of Execution
at the Cham Group, Roland Regli, who oversees all planning and construction on the site. Their job is to implement the client’s target of helping to reduce greenhouse gas emissions. The duo discuss how the various sustainable systems work and how the people who will live, work and spend time in the Papieri development will benefit from them.
“In a construction project, the architect usually plans the specific property first. This can be used to calculate how much energy is required. An appropriate energy system is then developed according to the specifications,” explains Georg Dubacher. A completely different approach was deliberately chosen for the Papieri development. Right from the start, the client, the Cham Group, wanted to play its part in the energy transition and contribute toward climate targets, while also taking account of the living comfort of future residents. In practical terms, this means how warm – and how cool – it should be in a closed room, based on individual needs.
And how this could be achieved without damaging the environment. Georg Dubacher has developed an optimal, completely carbon-neutral system concept based on these specifications. The architectural design could only really get underway once this concept had been pinned down. In this case, the building is based on the energy system, not the other way around. It is unique in this respect.
This was possible was not only due to the commitment of the Cham Group, but also the advantages of the Papieri neighborhood’s location along the river, which provided an area of the requisite size and ideal soil conditions for geothermal probes.
“We were able to develop a perfectly closed circuit for heating and cooling thanks to the existing energy sources.”
Georg Dubacher
But how does the system work, exactly? Essentially, it consists of a natural heat-cold cycle: heat is extracted from the ground using geothermal probes 320 meters deep. These geothermal probes and the warmth of the river water together provide the required heat. The soil cools down due to the heat extraction. In summer, the system works the other way round: the cooler soil can be used to cool the rooms. This in turn warms up the soil so that enough heat is available again for the colder months. The ground serves as a huge natural store of heat and cold.
The Cham Group also made it their stated aim from the very start to produce as much of the energy required as possible on the site itself. For this purpose, they designed their own power grid, similar in size to that of a small town. Almost half of the necessary electricity is produced on site, with around 50% of it coming from the river hydro power plant on the Lorze, which is currently being upgraded. The old wooden turbines are being retired, and one of them will be exhibited at a later date, in witness to the past. To obtain the very first concession to operate a river hydro power plant in the canton, the Cham Group provided various pieces of environmental evidence that showed that the new power plant would be more beneficial than detrimental to nature on balance. Fish and beaver ladders will be built to ensure that these creatures can move freely up and down the river. A large area in the north part of the site is also being renatured and left untouched.
Another 50% of the electricity is produced by photovoltaic systems on the roofs of the new buildings, with the rest coming from the public grid, with carbon-neutral measures in place. Thanks to this ingenious system, the electricity generated can be sold on to all users on the site at low cost. “The smart home solution brings this intelligent, complex networking system into every single room. It’s a highly future-oriented approach, and unique in Switzerland,” says Roland Regli.
Not only does the Papieri development reap the benefit of these solutions, but the entire region, too: if urban districts or neighborhoods can supply themselves with energy independently, this takes the pressure off regional and cross-regional networks and reduces inefficient energy transport routes and reliance on fossil fuels from abroad.
“Self-sufficient energy clusters will prove very important in the future as we seek to achieve our climate goals, as they also take a lot of pressure off the cross-regional power supply.”
Roland Regli
“There are not yet any standards governing home cooling in Switzerland. We can do it without consuming much energy, and with zero carbon emissions. The Papieri development is geared toward the targets of the 2000-watt society concept,” explains Georg Dubacher. Per capita consumption of energy in Switzerland is still around 8,000 watts. The energy system deployed by the Papieri neighborhood represents a real contribution toward controlling consumption in a self-driven way. The touch panel for the smart home solution within an apartment or the app allows individual residents to see how close they are to the 2000-watt target. Studies have shown that this visibility significantly increases willingness to optimize one’s own energy consumption.
“I’m delighted that when we were asked at the start of the site development whether we thought we could do without fossil fuels altogether, we answered yes. The energy supply on the Papieri site is completely carbon neutral and is enabling us to implement the goals of the 2000-watt society concept. The entire planning for the energy system, including initial partial implementation, took just three years.” - Roland Regli
Sustainable living is made even simpler by smart building envelopes with an automatic shading system. The blinds are automatically closed at night in winter, for example, to reduce heat loss. In summer, they can be kept closed so that apartments heat up less. Sustainable mobility has also been taken into consideration. Publicly accessible charging points in the garages and ultra-fast charging stations for turbo charging on the Papieri ring road – the current access road to the site – help reduce CO2 consumption.
“I’m incredibly proud that we’ve been able to achieve a high level of energy self-sufficiency. The construction and planning process is far more arduous, but the operating costs for the sustainable energy system are streamlined and efficient; finally there’s no longer any need to order oil,” laughs Georg Dubacher.
